This invention relates to encapsulation of magnetic heads, and particularly to a process for encapsulating magnetic heads with diamond-like carbon, as well as the resulting structure.
Thin film magnetic transducing heads employ a pair of magnetic poles separated, at the air-bearing surface, by a thin film of insulating material. In inductive transducers, the body of the transducing head employs a plurality of coil segments passing therethrough, also embedded in insulating material. Thus in a write head, current passing through the coil induces changes in the magnetic field in the poles, causing magnetic flux adjacent the gap, thereby altering the magnetic domains in an adjacent magnetic disc. In an inductive read head, changes in the magnetic flux adjacent the gap due to the rotating magnetic disc induce changes in the magnetic field in the poles, which in turn induces or alters an electric signal in the coils. Typically, the head is mounted to a substrate, with the several convolutions of the coil terminating in at least a pair of electrical pads for connection to the read/write circuits of the disc drive. The substrate is mounted on an actuator arm for positioning adjacent the rotating magnetic disc.
It is common to encapsulate thin film inductive magnetic heads to protect them from the corrosive effects of water and other contaminates during subsequent processing of the head or during use. For example, wet etchants, solvents and developing agents used in subsequent processing of the head can attack the head. Therefore, it is common to encapsulate the head as early as possible and prior to subsequent processing. Prior encapsulation materials included oxide insulators such as SiO.sub.2 and Al.sub.2 O.sub.3. The difficulty with such insulating material is that pinholes formed in the material allowing entrance of contaminates, etchants and developing agents. Even with encapsulation layers that are quite thick, such as several thousand Angstroms, a risk exists that contaminates, etchants and developing agents will penetrate the encapsulation layer and attack the head.
There is, accordingly, a need for an encapsulation technique for a thin film head that is not susceptible to the etchants ordinarily employed in the formation of the head.